They choosed to play the bishop exchange openning and Habu tried the rushing silver variation.

The king of Satou is still in the center of the board and can be attacked. This openning looks for a fast attack before the king can be protected.

In this position Satou thrown away his bishop in exchange of Habu’s silver to dilute the defence of Habu king. With that move the only piece that keeps near for defend the critical point 2c is the gold that will be perturbed by pawns.